US-20260129745-A1 - CIRCUIT BOARD STRUCTURE AND MANUFACTURING METHOD THEREOF

Abstract

A circuit board structure and a manufacturing method thereof are provided. The circuit board structure includes a base layer, a first circuit layer, a support material layer, a build-up material layer, and a second circuit layer. The first circuit layer is disposed on the base layer. The support material layer is disposed on the base layer and on one side of the first circuit layer. The build-up material layer is disposed on the first circuit layer and the support material layer. The second circuit layer is disposed on the build-up material layer.

Inventors

• Ching-Sheng Chen
• Chi-Min Chang
• Wei-Yu Liao
• Chun-Jui Huang
• Yi-Pen Lin

Assignees

• UNIMICRON TECHNOLOGY CORP.

Dates

Publication Date

20260507

Application Date

20241204

Priority Date

20241104

Claims (20)

1. 1 . A circuit board structure, comprising: a base layer; a first circuit layer disposed on the base layer; a support material layer disposed on the base layer and located on one side of the first circuit layer; a build-up material layer disposed on the first circuit layer and the support material layer; and a second circuit layer disposed on the build-up material layer.
2. 2 . The circuit board structure as claimed in claim 1 , wherein the base layer comprises a first region and a second region, and a ratio of an area of the first circuit layer located on the first region to a total area of the first region is less than a ratio of an area of the first circuit layer located on the second region to a total area of the second region, wherein the support material layer is located at least in the first region.
3. 3 . The circuit board structure as claimed in claim 2 , wherein the ratio of the area of the first circuit layer located on the first region to the total area of the first region is less than 50%.
4. 4 . The circuit board structure as claimed in claim 1 , wherein an upper surface of the first circuit layer and an upper surface of the support material layer are coplanar.
5. 5 . The circuit board structure as claimed in claim 1 , wherein an upper surface of the build-up material layer located on the support material layer and an upper surface of the build-up material layer located on the first circuit layer are coplanar.
6. 6 . The circuit board structure as claimed in claim 1 , wherein a material of the support material layer comprises epoxy, silicon dioxide, bisphenol F, epichlorhydrin, a copolymer thereof, or a combination thereof.
7. 7 . The circuit board structure as claimed in claim 1 , wherein a material of the support material layer is the same as a material of the build-up material layer.
8. 8 . The circuit board structure as claimed in claim 1 , wherein a thickness of the support material layer is between 0.01 mm and 0.12 mm.
9. 9 . The circuit board structure as claimed in claim 1 , wherein the support material layer is not in direct contact with the first circuit layer.
10. 10 . The circuit board structure as claimed in claim 9 , wherein a shortest distance between the support material layer and the first circuit layer is greater than 0.03 mm.
11. 11 . The circuit board structure as claimed in claim 9 , wherein the build-up material layer is located between the support material layer and the first circuit layer.
12. 12 . The circuit board structure as claimed in claim 11 , wherein the base layer and the build-up material layer completely surround the first circuit layer.
13. 13 . A manufacturing method of a circuit board structure, comprising: providing a base layer; disposing a first circuit layer on the base layer; disposing a support material layer on the base layer, wherein the support material layer is located on one side of the first circuit layer; disposing a build-up material layer on the first circuit layer and the support material layer; and disposing a second circuit layer on the build-up material layer.
14. 14 . The manufacturing method of the circuit board structure as claimed in claim 13 , wherein the step of forming the support material layer comprises: coating a support material on the base layer; and performing a prebaking process and a baking process to form the support material into the support material layer.
15. 15 . The manufacturing method of the circuit board structure as claimed in claim 14 , wherein the support material is not in direct contact with the first circuit layer.
16. 16 . The manufacturing method of the circuit board structure as claimed in claim 15 , wherein a shortest distance between the support material and the first circuit layer is greater than 0.03 mm.
17. 17 . The manufacturing method of the circuit board structure as claimed in claim 13 , wherein the base layer comprises a first region and a second region, and a ratio of an area of the first circuit layer located on the first region to a total area of the first region is less than a ratio of an area of the first circuit layer located on the second region to a total area of the second region, wherein the support material layer is located at least in the first region.
18. 18 . The manufacturing method of the circuit board structure as claimed in claim 17 , wherein the ratio of the area of the first circuit layer located on the first region to the total area of the first region is less than 50%.
19. 19 . The manufacturing method of the circuit board structure as claimed in claim 13 , wherein an upper surface of the build-up material layer located on the support material layer and an upper surface of the build-up material layer located on the first circuit layer are coplanar.
20. 20 . The manufacturing method of the circuit board structure as claimed in claim 13 , wherein a material of the support material layer comprises epoxy, silicon dioxide, bisphenol F, epichlorhydrin, a copolymer thereof, or a combination thereof.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This Application claims priority of Taiwan Patent Application No. 113142170, filed on Nov. 4, 2024, the entirety of which is incorporated by reference herein. BACKGROUND OF THE INVENTION Field of the Invention The present disclosure relates to a circuit board structure and, in particular, to a circuit board structure in which a support material layer is disposed between a build-up material layer and a base layer and a manufacturing method of the circuit board structure. Description of the Related Art As the application of electronic products becomes more widespread, electronic products are required to have higher performance. For example, in order to meet high-frequency applications, circuit board structures in electronic products need to have better impedance matching and signal integrity. However, some defects in the circuit board structures may lead to poor impedance matching and signal integrity. These defects include uneven thickness and material mismatch, among others. Therefore, although existing circuit board structures have largely met their intended purposes, they do not meet requirements in all respects. Therefore, there is still a need to develop new circuit board structures and manufacturing methods thereof. BRIEF SUMMARY OF THE INVENTION In some embodiments of the present disclosure, a circuit board structure is provided. The circuit board structure includes a base layer, a first circuit layer, a support material layer, a build-up material layer, and a second circuit layer. The first circuit layer is disposed on the base layer. The support material layer is disposed on the base layer and on one side of the first circuit layer. The build-up material layer is disposed on the first circuit layer and the support material layer. The second circuit layer is disposed on the build-up material layer. In some embodiments of the present disclosure, the base layer includes a first region and a second region, and the ratio of the area of the first circuit layer located on the first region to the total area of the first region is less than the ratio of the area of the first circuit layer located on the second region to the total area of the second region, wherein the support material layer is located at least in the first region. In some embodiments of the present disclosure, the ratio of the area of the first circuit layer located on the first region to the total area of the first region is less than 50%. In some embodiments of the present disclosure, the upper surface of the first circuit layer and the upper surface of the support material layer are coplanar. In some embodiments of the present disclosure, the upper surface of the build-up material layer located on the support material layer and the upper surface of the build-up material layer located on the first circuit layer are coplanar. In some embodiments of the present disclosure, the material of the support material layer includes epoxy, silicon dioxide, bisphenol F, epichlorhydrin, a copolymer thereof, or a combination thereof. In some embodiments of the present disclosure, the material of the support material layer is the same as the material of the build-up material layer. In some embodiments of the present disclosure, the thickness of the support material layer is between 0.01 mm and 0.12 mm. In some embodiments of the present disclosure, the support material layer is not in direct contact with the first circuit layer. In some embodiments of the present disclosure, the shortest distance between the support material layer and the first circuit layer is greater than 0.03 mm. In some embodiments of the present disclosure, the build-up material layer is located between the support material layer and the first circuit layer. In some embodiments of the present disclosure, the base layer and the build-up material layer completely surround the first circuit layer. In some embodiments of the present disclosure, a manufacturing method of a circuit board structure is provided. The manufacturing method includes the following steps. A base layer is provided. A first circuit layer is disposed on the base layer. A support material layer is disposed on the base layer, wherein the support material layer is located on one side of the first circuit layer. A build-up material layer is disposed on the first circuit layer and the support material layer. A second circuit layer is disposed on the build-up material layer. In some embodiments of the present disclosure, the step of forming the support material layer includes the following steps. A support material is coated on the base layer. A prebaking process and a baking process is performed to form the support material into the support material layer. In some embodiments of the present disclosure, the support material is not in direct contact with the first circuit layer. In some embodiments of the present disclosure, the shortest distance between the support material and the